Problem: $ { \left[\begin{array}{rrr}{1} & {4} & {0} \\ {4} & {-1} & {2}\end{array}\right]+\left[\begin{array}{rrr}{-1} & {0} & {1} \\ {-1} & {2} & {1}\end{array}\right] = {?} } $
Solution: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{1}+{-1} & {4}+{0} & {0}+{1} \\ {4}+{-1} & {-1}+{2} & {2}+{1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{0} & {4} & {1} \\ {3} & {1} & {3}\end{array}\right]}$